Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, School of Life Science, South China Normal University, 510631 Guangzhou, China.
Agriculture and Agri-Food Canada, London Research and Development Centre, London, ON N5V 4T3, Canada.
Plant Commun. 2020 Jul 2;2(1):100091. doi: 10.1016/j.xplc.2020.100091. eCollection 2021 Jan 11.
The post-translational protein modification known as SUMOylation has conserved roles in the heat stress responses of various species. The functional connection between the global regulation of gene expression and chromatin-associated SUMOylation in plant cells is unknown. Here, we uncovered a genome-wide relationship between chromatin-associated SUMOylation and transcriptional switches in grown at room temperature, exposed to heat stress, and exposed to heat stress followed by recovery. The small ubiquitin-like modifier (SUMO)-associated chromatin sites, characterized by whole-genome ChIP-seq, were generally associated with active chromatin markers. In response to heat stress, chromatin-associated SUMO signals increased at promoter-transcriptional start site regions and decreased in gene bodies. RNA-seq analysis supported the role of chromatin-associated SUMOylation in transcriptional activation during rapid responses to high temperature. Changes in SUMO signals on chromatin were associated with the upregulation of heat-responsive genes and the downregulation of growth-related genes. Disruption of the SUMO ligase gene abolished SUMO signals on chromatin and attenuated rapid transcriptional responses to heat stress. The SUMO signal peaks were enriched in DNA elements recognized by distinct groups of transcription factors under different temperature conditions. These observations provide evidence that chromatin-associated SUMOylation regulates the transcriptional switch between development and heat stress response in plant cells.
蛋白质翻译后的修饰过程中，SUMO 化作用在各种物种的热应激反应中起着保守的作用。在植物细胞中，基因表达的全局调控与染色质相关 SUMO 化之间的功能联系尚不清楚。在这里，我们在室温下生长的细胞中发现了染色质相关 SUMO 化和转录开关之间的全基因组相关性，这些细胞既经历了热应激，又经历了热应激后的恢复。通过全基因组 ChIP-seq 对与小泛素样修饰物 (SUMO) 相关的染色质位点进行了特征描述，这些位点通常与活跃的染色质标记物相关联。在热应激反应中，染色质相关的 SUMO 信号在启动子-转录起始位点区域增加，而在基因体中减少。RNA-seq 分析支持了染色质相关 SUMO 化在快速响应高温时转录激活中的作用。染色质上 SUMO 信号的变化与热响应基因的上调和生长相关基因的下调有关。SUMO 连接酶基因的破坏导致染色质上的 SUMO 信号消失，并减弱了对热应激的快速转录反应。在不同温度条件下，SUMO 信号峰富集在不同转录因子组识别的 DNA 元件中。这些观察结果为染色质相关 SUMO 化调节植物细胞中发育和热应激反应之间的转录开关提供了证据。
